From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Andrzej Siewior Subject: Re: [PATCH v8 00/18] 8250-core based serial driver for OMAP + DMA Date: Wed, 10 Sep 2014 18:56:37 +0200 Message-ID: <541082C5.7040608@linutronix.de> References: <1409943773-7874-1-git-send-email-bigeasy@linutronix.de> <20140908144616.GA22315@ci00147.xsens-tech.local> <20140908151501.GA22584@linutronix.de> <20140908183353.GB4686@ci00147.xsens-tech.local> <540F57E0.8030404@linutronix.de> <20140910141554.GC22315@ci00147.xsens-tech.local> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from www.linutronix.de ([62.245.132.108]:34360 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751077AbaIJQ4s (ORCPT ); Wed, 10 Sep 2014 12:56:48 -0400 In-Reply-To: <20140910141554.GC22315@ci00147.xsens-tech.local> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Frans Klaver Cc: linux-serial@vger.kernel.org, tony@atomide.com, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, balbi@ti.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org On 09/10/2014 04:15 PM, Frans Klaver wrote: > On Tue, Sep 09, 2014 at 09:41:20PM +0200, Sebastian Andrzej Siewior wrote: >> On 09/08/2014 08:33 PM, Frans Klaver wrote: >>> Thanks. I'll give it a spin on Wednesday. >> >> Could you please pull the upcoming v9 first? >> >> git://git.breakpoint.cc/bigeasy/linux.git uart_v9_pre1 >> >> This solves a few of my am335x related issues. > > Using v9_pre1, I get a kernel panic in edma_dma_pause() on echan->edesc > being NULL. I do get data before this happens. This is at high speed, > high rate. No mention of the irq having too much to do, though. The more > data I transmit, the more likely this is to occur. Hmm. This shouldn't happen because if dma->rx_running is set, then there should be a descriptor to pause. Could check how this could happen? (and which event tries to do so) In the meantime, the lower part of [0] should fix the NULL bug. [0] https://lkml.org/lkml/2014/7/29/506 > I don't currently have the setup to lower the baudrate. I would probably > need to reproduce this on a beaglebone, instead of our custom board. > I'll see if I can do that. > > If you need more info, just let me know. I just pushed uart_v9_pre2 and I will post it once I rebased it on top Greg's latest. There was a bug where THRE could be active longer than needed caused a few not needed interrupts until the FIFO was empty again. My "less on file" test case did not fail anymore with this. > Thanks, > Frans Sebastian